This invention relates to CAD/CAM devices (computer-aided design/computer-aided manufacturing devices), and more particularly to CAD/CAM devices by which the information for generating the data for numerically controlled devices is maintained hierarchically.
FIG. 9 is a block diagram showing the organization of a conventional CAD/CAM device.
The data are input via a keyboard 1, a mouse 2 or a tablet 3. The input data via the keyboard 1, the mouse 2, or the tablet 3 are interpreted by an input processing module 4 and then are transferred to the interior units. A figure processing module 85 defines and edits figure elements, such as points, lines, circles, dimension lines, and legends, or three-dimensional curves. Figure data 86 are thus generated via the figure processing module 85.
A work step processing module 90 defines and edits the work step data 91 needed for generating control data for a numerically controlled device such as a machine tool (not shown). A work path processing module 92 generates various figures and work paths and displays them on a CRT display unit 14. A NC data generator module 93 generates the NC data 15 for working a piece of work in accordance with the defined girure. The paths of the tool indicated by the NC data 15 thus generated by the NC data generator module 93 are displayed on the screen.
Next, the operation of the CAD/CAM device of FIG. 9 is described.
Consulting the display on the CRT display unit 14, the operator prepares various figures interactively via the keyboard 1, the mouse 2, or the tablet 3. Next, the operator selects the figure for the work path by inputting the name of the figure via the keyboard 1 or by pointing the figure by means of the mouse 2. Further, the operator sets the work step data 91 with respect to the figure data 86. The NC data generator module 93 then generates the NC data 15 by referencing the work step data 91.
The above CAD/CAM device has the following disadvantage. The data for the figure elements such as points, lines, circles, and curves, the data for three-dimensional curves, and the data for three-dimensional forms are maintained separately from each other. Thus, although the figure elements, three-dimensional curves, and three-dimensional forms are displayed without clear distinctions from each other on the screen, the operations to be performed by the operator for displaying, searching, and modifying them are distinct from each other. The operator may thus be confused. Further, it is difficult to treat pieces of data having the same attribute via a single operation. For example, the pieces of data having the same attribute cannot be searched by a single operation. Furthermore, the amount of work required from the preparation of drawings of the figures to the generation of the NC data is large.